In order to maximise excavation and mineral recovery efficiency, mining machines have been developed for specific purposes. Whilst some machines are configured exclusively to cut the mineral from a deposit or seam, other machines are configured to tunnel within the subterranean depth to effectively create the mine and provide passageways for the mineral cutters. In particular, mobile mining machines have emerged as successful apparatus to both provide direct cutting at the seam and as a means of rapid entry roadway development. For example, a mobile mining machine comprises a rotatable cutting or mining head having cutting bits provided on rotating drums to contact the mineral face. The cutting head is conventionally mounted at a moveable boom so as to be adjustable in height relative to the mine floor. As the cutting head is rotated and advanced into the seam, the extracted mineral is gathered by a gathering head and then conveyed rearwardly by the mobile machine via conveying apparatus to create discharged stock piles for subsequent extraction from the mine.
Those machines that are adapted to create the mine passageways are typically fitted with roof and rib bolting rigs. The roof and rib bolts reinforce the roof and walls of the mine by interconnection with reinforcement formations. Due to the confined space in which the machine is operating, the bolting rigs are typically positioned immediately behind the cutting head and are required to be as small as possible whilst allowing access for personnel to interchange the drill rod used to create the borehole and the roof or rib bolt that is then driven into the as formed hole. Other mobile machines that employ drill and/or bolting rigs include dedicated bolters, roadheaders, platform bolters and the like. Example drill and bolting rigs are described in US 2003/066665; DE 102007038265; EP 1533470 and EP 0470061.
As will be appreciated, it is typically required to take out the drill rod to one side of the drilling centre whilst the bolt is installed into the borehole. Conventional arrangements are disadvantageous as they restrict access to the drill unit making it difficult to interchange the rod and bolt. Additionally, conventional rigs are typically bulking and are not easily accommodated in the restricted space available at the mining machine. Accordingly, what is required is a mining bolting drill rig that solves these problems.